A solid catalyst component that includes magnesium, titanium, internal electron donor, a halogen as essential components has been used when polymerizing an olefin (e.g., propylene). A number of methods that polymerize an olefin or copolymerize olefins in the presence of an olefin polymerization catalyst that includes the solid catalyst component, an organoaluminum compound, and an organosilicon compound, have been proposed.
On the other hand, a solid catalyst component that includes magnesium, titanium, vanadium, a halogen as essential components has been used when copolymerizing olefins (e.g., ethylene and propylene). A number of methods that polymerize an olefin or copolymerize olefins in the presence of an olefin polymerization catalyst that includes the solid catalyst component and an organoaluminum compound have been proposed.
Catalyst systems that include titanium compounds and vanadium compounds have been proposed to produce excellent copolymer, especially for random copolymer components from ethylene and propylene. The prior arts are as follows;
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